A set of patches to Ruby MRI 1.9.3 and 1.9.2 that adds run-time introspection, a call frame object, and other run-time support for things like debuggers.
For MRI 1.9.2, there are additional routines are in a C extension. For MRI 1.9.3, everthing is in a patched Ruby. Necessary patches and some simple patch code are found in this repository though. See https://github.com/rocky/rb-threadframe/wiki/How-to-Install for how to install.
Source for Ruby MRI version 1.9.2 or 1.9.3 p327. Patches are provided for these two versions only.
See the wiki for more information.